Primary Prevention with Defibrillator Therapy in Women: Results from the Sudden Cardiac Death in Heart Failure Trial

Authors


  • This article was processed by a guest editor.

  • Research support was provided by Medtronic to Drs. Bardy, Lee, Mark, and Russo; Boston Scientific and St. Jude Medical to Dr. Russo; Biotronik to Dr. Poole; and Wyeth-Ayerst and NIH to Dr. Bardy for ScD-HeFT.

  • Dr. Russo received honoraria from Boston Scientific, Medtronic, and St. Jude Medical. Dr. Poole received compensation for participation in a speaker's bureau for Boston Scientific and Medtronic. Dr. Bardy has patents and equity in Cameron Health.

  • Manuscript received 18 November 2007; Revised manuscript received 16 December 2007; Accepted for publication 19 December 2007.

Address for correspondence: Andrea M. Russo, M.D., University of Pennsylvania Health System, Penn-Presbyterian Medical Center, 4th Floor PHI, 38th and Market Streets, Philadelphia, PA 19104, USA. Fax: 215-243-3264; E-mail: andrea.russo@uphs.upenn.edu

Abstract

Introduction: The Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) demonstrated that implantable cardioverter defibrillator (ICD) therapy reduced overall mortality in patients with class II or III heart failure and left ventricular ejection fraction (LVEF) ≤ 35%, while amiodarone had no effect on survival. There are limited data regarding the influence of gender on outcome of patients receiving ICDs for primary prevention.

Methods: We examined gender differences in response to treatment and outcome in this cohort.

Results: Women comprised 23% of the SCD-HeFT cohort, with similar percentages in the amiodarone, ICD, and placebo groups. Compared with men, women were more likely to be non-Caucasian, to have class III heart failure, and nonischemic heart disease. After adjustment for baseline differences, overall mortality risk was lower in women than in men. The gender difference in overall mortality was seen in the placebo group, while no gender difference in overall mortality was seen in the ICD group. There was a significantly lower absolute risk of death in the placebo arm women, compared with the placebo arm men (annual mortality rate approximately 4% vs. 6%).

Conclusions: The impact of ICD therapy appears to differ between men and women in this trial, with a smaller ICD benefit among women. However, the test for an interaction between gender and therapy was not significant. The lower overall mortality risk in women in the placebo group and the smaller number of women enrolled may help to explain why treatment differences in women were much smaller and difficult to detect.

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